At last: The numerical limit. Each pixel is 40nm, and the intersection process comes into first troubles. Though not obvious in the image, some intersections are lost due to numerical instabilities. Nethertheless the absolute limit would be 10^-10, about even 400 times smaller than this last image of this zoom serie. But due to unavoidable tolerances, this atomic size is beyond the useable limit. Just not note finally, that the useable limit already is far beyond the senseful limit...
Computation time: 000d 05h:47m:24s